diff --git a/cpu/sh4/Makefile b/cpu/sh4/Makefile
index aaaaf1f..6192913 100644
--- a/cpu/sh4/Makefile
+++ b/cpu/sh4/Makefile
@@ -28,19 +28,27 @@
 
 LIB	= $(obj)lib$(CPU).a
 
-START	= start.o
+SOBJS	= start.o
 OBJS	= cpu.o interrupts.o watchdog.o time.o cache.o
 
-all:	.depend $(START) $(LIB)
+SRCS	:= $(SOBJS:.o=.S) $(COBJS:.o=.c)
+OBJS	:= $(addprefix $(obj),$(COBJS))
+SOBJS	:= $(addprefix $(obj),$(SOBJS))
 
-$(LIB):	$(OBJS)
-	$(AR) $(ARFLAGS) $@ $(OBJS)
+$(LIB):	$(OBJS) $(SOBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS) $(SOBJS)
+
+clean:
+	rm -f $(SOBJS) $(OBJS)
+
+distclean:	clean
+	rm -f $(LIB) core *.bak .depend
 
 #########################################################################
 
-.depend:	Makefile $(START:.o=.S) $(OBJS:.o=.c)
-		$(CC) -M $(CFLAGS) $(START:.o=.S) $(OBJS:.o=.c) > $@
+# defines $(obj).depend target
+include $(SRCTREE)/rules.mk
 
-sinclude .depend
+sinclude $(obj).depend
 
 #########################################################################